Even though the human race is essentially the same as we are all humans, different people have different biological races. There are many types of human races and each race depends on the backgrounds of the parents, where they live in the world and their ethnicity. So, <span>"biological race" is an evolutionarily valuable way to describe human variation. </span>
When there are not many sellers of a item the price of the item goes up because not many people have that item or sell it and the fewer the people that sell that item the more money the people make that have it and it makes it harder to get.
Other water gets contaminated and it spreads,